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Applied Math Seminar: Conformational changes at the nucleotide site of myosin and kinesin motors
2007-04-10
4:10 PM, Webster B8
Ed Pate
ABSTRACT: The hydrolysis of ATP provides the free energy for the generation of biologically useful motion by kinesin and myosin motor proteins. Angstrom magnitude conformational changes at the nucleotide site associated with hydrolysis are propagated to peripheral elements of the proteins where they are amplified into nanometer size steps of motion. How this occurs remains unexplained. Resolution of the mechanism will require understanding the sequence of protein conformational changes that are involved. We have used electron paramagnetic resonance spectroscopy to probe conformational changes at the ATP binding site of kinesin and myosin motors. Myosin translocates along actin filaments. Kinesin moves along microtubules. Our results show that the closed nucleotide site seen in myosin x-ray structures opens when myosin binds strongly to actin. Conversely, the open nucleotide site seen in kinesin x-ray structures closes when kinesin binds to microtubules. The two motors have evolved from a common ancestor protein, and the distinct open/closed x-ray structures of each appear to be additionally capturing a conformation of the other. Molecular dynamics simulations are used to better understand the spectroscopic observations in terms of available x-ray structures and homologies between the two classes of motors. The results provide structural explanations for relationships between the isolated motor biochemical cycles and functioning mechanical cycles. Additionally, the results fill in gaps in the crystallographic observations of the motor proteins.
Weekly Scheduled Seminars
For more information please contact the individuals listed below.Monday
1:10pmAlgebra Seminar - Google Group
Neill Hall 106W
Contact: Judi McDonald
Tuesday
4:30-5:30pmMathematics Education Seminar
One World Cafe - Moscow, ID
Contact: Libby Knott
Wednesday
3:00-4:00pmApplied Math Seminar
Neill Hall 3W
Contact: Alan Genz
4:00-5:00pm
Reliability and Risk Seminar
Neill Hall 106W
Contact: Haijun Li
Thursday
Friday
4:15-5:15pmSpatial Reasoning: An Interdisciplinary Seminar
Cleveland Annex 309
Contact Co-organizers: Kim Vincent and Kathleen Ryan, Interior Design.
Various disciplines dealing with spatial relationships and reasoning will be examined. We will discuss what spatial reasoning is and how to improve students' spatial reasoning. The book, Learning to Think Spatially: GIS as a Support System in the K-12 Curriculum will be used. A read-only version may be found at www.nap.edu/catalog.php?record_id=11019